Shade Helps Compressor Keep Its Cool

Q--Is it important to shade the air conditioner compressor outside the house?

A--Shade keeps the condensing coil inside the compressor unit cooler and running more efficiently. It can make a big difference in the job your air conditioner does.

One common way to shade the unit is to install it on the north side of the house in an area where it will receive little direct solar radiation in the summer. The worst location is the west side, where the sun will strike it in late afternoon and evening, when it needs to work the most.

You can put shade trees near the unit, but be careful not to block airflow to and from the unit.

Q--We live in a warm climate area and don't use much heat in the winter. Could passive heat benefit us?

A--Sure. If you live in a part of the country where you don't use too much heating in winter, passive heating techniques may fill most--if not all--of your needs. Even if you live in a northern climate, such strategies can supplement your heating system and lower your energy bills.

The two basic strategies of passive heating are direct-gain and sun-tempering.

Direct-gain is the simplest technique. Sunlight enters the home through a large area of south-facing windows and strikes walls or floors that absorb heat. At night, as the room cools, the stored heat will radiate into the room.

Sun-tempering is the building strategy of using windows on the south side of the home. In a conventional home, about 25 percent of the windows face south, which generally amounts to about 3 percent of the home's total floor area. In a sun-tempered house, though, the percentage of south-facing glass is increased to a maximum of 7 percent of the total floor area. Taking the house plans and moving some windows from the other sides of the home to the south side gives the home more solar heat (and also reduces the summer cooling load) without adding cost for materials.

These techniques will work well for a new house. If you're looking at ways to use passive heating in your home, you can open blinds and drapes in winter to let the sun in and open passages between rooms to allow heat to flow easily. Also be sure you have sealed cracks and holes in walls and take other steps to make your home airtight.